Electro-endosmotic process of extracting sugar.



No. 723,928. I PATENTED MAR. '31, 1903.

v B. SGHWERIN. I ELEOTRO-BNDOSMOTIG PROCESS OF EXTRAGTING SUGAR.

APPLIOATION FILED NOV. 15, 1901.

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UNITED STATES PATENT OFFICE.

BOTHO SCHWERIN, OF BERLIN, GERMANY.

ELECTRO-ENDOSMOTIC PROCESS OF EXTRACTING SUGAR.

:EEECIFIGATION forming part of Letters Patent N 0. 723,928, dated March 31, 1903 Application filed November 15, 1901. Serial No. 82,430. (No specimens.)

To. all whorrt it may concern:

Be it known that I, BoTHo SOHWERIN, a

subject of the King of Prussia, German Em-.

peror, residing at No. 19 Bernburgerstrasse, Berlin, in the Kingdom of Prussia, German Empire, have invented certain new and useful Improvements upon the Electro-Endosmotic Process of Extracting Sugar; and I do hereby declare that the following is a full, clear, and exact description of my invention, which will enable others skilled in the art to which itappertainsto make and use the same.

This invention relates to the process of ex tracting sugar by acting with the electric current upon disintegrated wet saccharine material, which is placed between a negative electrode pervious'to liquid and a layer of water separating the positive electrode from the saccharine material, as fully described and claimed in my United'States Letters Pa t out No. 687,386, dated November 26, 1901.

It has for its object to improve the result of the Whole.

To this end it consists, first, in causing the albuminous matter to separate out at the negative electrode, so as to be prevented from leaving the apparatus, and, second, in converting the acids accumulating in the beginning of the process in the water at the positive electrode into indissoluble and innocuous compounds, as far as is possible.

As to the first improvement, this is obtained by causing the liquor to pass through a layer of finely-divided carbon located at one or both sides of the negative electrode. I prefer to use animal charcoal, (bone-black, animal-black,) which has proved to yield the v best result, even when applied in a very thin that it may at once be crystallized, the crystallized-out sugar being of asatisfactorily white color. Compared with the usual method of bone-blacking the raw-sugar solution, the advantage resulting from the introduction of a carbon layerin connection with the negative electrode consists in that directly a concentrated, pure, and almost, colorless solution fit for crystallization is obtained without the necessity of special costly apparatus and at a low cost, as only a thin layer of carbon is required and the liquor needs not to be heated, and, moreover, the loss of sugar occurring in replacing the layer is an extremely small one.

The second improvement is obtained by suspending in the water in which the positive electrode is immersed finely-powdered earthy compounds-that is to say, oxids or carbonates of alkaline earth or earth metals, such as calcium, barium, strontium, magnesium, aluminium, and the like, said oxids or carbonates reacting with the acids that ap-- pear at the positive electrode to form salts, .1

which for the greater part are insoluble in water. By these means I provide for a very efficient protection of the positive pole against chemical decomposition, and, on the otherhand, I prevent the water from being infected with substances which after some accumulation or in the progress of the treatment might diffuse back intothe saccharine material, with the result of producing invertsugar or otherwise impurifying the sugarsolution: I In realizing my said improvements I profor to arrange the saccharine material in a ICO horizontal layer, with the negative electrode made out of wire-gauze-for instance, copper-wire gauze--applied against its under side. I first place the wire-gauze and then cover the same with a filtering-cloth. On the latter I provide a 'thin layer of powdered carbonfor instance, by evenly spreading out thereon dust of bone-black-which I cover with another filtering-cloth. On the latter I place the saccharine material to be treated for instance, slices of beet-root or disinte-- grated sugar-cane-and cover the same with a filtering-cloth. On the latterI provide a layer of water mixed with finely-powdered magnesium oxid or calcium carbonate or other suitable earthy compounds, and in this mixture I immerse in horizontal position a metal platefor instance, an iron plateto serve as the positive electrode.

In order to fully enable those skilled in the art to use my said improvements, I have illustrated on the annexed sheet a diagrammatical section of an apparatus for carrying them out into practice.

1 is a box preferably of square shape and made out of an electrically-non-conductive material-as, for instance, wood-which is open at the top and provided at its bottom with an opening 2 for the outflow of the sugar solution. Near the upper edge of the box are fixed at theinside supports 3 for the wire-gauze 4 and the layer of carbon 6 held between filter-cloths 5 and 7. When the wire-gauze and carbon layer are placed, a frame 8, constructed with an electrically-nonconductive material, preferably wood, and closely fitting in the box 1, is inserted into the latter so as to firmly clamp the wiregauze, filtering-cloths, and interposed carbon layer between its lower edge and the supports 3. The frame is then filled with the saccharine material 9 up to a distance from its upper edge, said material covered with a filtering-cloth 10, a mixture 11 of water and earthy compound or compounds for instance, calcium carbonate or magnesium oxid--poured in the space left above the filtering-cloth l0, and the metal plate 12, which is hung from a carrier (not shown) lowered so as to be suspended within the mixture of water and earthy compound. The plate 12 and the wire-gauze at are connected,the former with the positive and the latter with the negative pole of the dynamo or other source of electricity. The numeral 13 denotes a cock for supplying water to replace that which is driven through the cloth 10 into the saccharine material 9.

I wish it to be understood that the term disintegrated as used in connection with the term saccharine material is intended to express in a broad sense any sufficient degree of subdivision and that the term earthly compound is intended to comprise oxide and carbonates of the alkaline-earth metals and earth metals, as in connection with the use made of them they have proved to be true equivalents.

What I claim, and desire to secure by Letters Patent of the United States, is-

1. The process of extracting sugar which consists in placing the saccharine material to be treated in a disintegrated and wet state between a layer of finely-divided carbon supported by a negative electrode pervious to liquid and a. body of water surrounding the positive electrode, driving the electrolytically non-dissociable liquid bodies present toward the negative electrode by passing a current through the said layer of water, material and layer of carbon by means of said electrodes, supplying the water driven into the material from the water surrounding the positive electrode, collecting the liquor percolating through the layer of carbon and its supporting negative electrode, and separating there from sugar, substantially as and for the purpose specified.

2. The process of extracting sugar which consists in placing the saccharine material to be treated in a disintegrated and wet state between a negative electrode pervious to liquid and a mixture of water and earthy compounds surrounding a positive electrode, driving the electrolytically non-dissociable liquid bodies present toward the negative electrode by passing a current through the said layer of water and material by means of said electrodes, supplying the water driven into the 'material from the water surrounding the positive electrode, collecting the liquor percolating through the layer of carbon and its supporting negative electrode, and separating therefrom sugar, substantially as and for the purpose specified.

3. The process of extracting sugar which consists in placing the saccharine material to be treated in a disintegrated and wet state between a layer of finely-divided carbon supported by a negative electrode pervious to liquid and a mixture of water and earthy compounds surrounding a positive electrode, driving the electrolytically non-dissociable liquid bodies present toward the negative electrode by passing a current through the said layer of water, material and layer of carbon by means of said electrodes, supplying the water driven into the material from the water surrounding the positive electrode, collecting the liquor percolating through the layer of carbon and its supporting negative electrode, and separating therefrom sugar, substantially as and for the purpose specified.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

BOTHO SCHWERIN. Witnesses:

H. R. MCGINNIS, ANNIE VVIMBAUER. 

